1.下载jdk8安装包

https://www.oracle.com/java/technologies/javase/javase-jdk8-downloads.html

2.上传到服务器  /usr/local/ 目录

3.进入目录

cd /usr/local/

4.解压

tar -zxvf jdk-8u291-linux-x64.tar.gz

5.配置环境变量

vim /etc/profile

6.追加配置

# jdk8 config
export JAVA_HOME=/usr/local/jdk1.8.0_291
export CLASSPATH=.:${JAVA_HOME}/jre/lib/rt.jar:${JAVA_HOME}/lib/dt.jar:${JAVA_HOME}/lib/tools.jar
export PATH=$PATH:${JAVA_HOME}/bin

7.刷新环境变量配置

source /etc/profile

8.查看jdk版本

java -version